Investigating the role of mesenchymal R-Spondin2 during human lung development

项目摘要 哺乳动物呼吸系统的发育受复杂的相互作用的信号事件调节 位于呼吸道衬里的上皮细胞和周围间充质细胞之间。尽管肺部不适 间充质是在发育过程中提供关键信号的细胞类型的家园，身份和 肺间充质中特定细胞类型的功能尚未明确，尤其是在人类的情况下。 发展。为了研究发育中的人肺间充质细胞的异质性，我们的实验室 对怀孕8-22周的多个人肺样本进行了单细胞RNA测序。 使用细胞聚集的方法，我们鉴定了一个高度丰富表达的间充质细胞群。 WNT激动剂R-Spin2(RSPO2)。引人注目的是，该基因的突变会导致严重的肺再生障碍性贫血 人类。人肺组织的荧光原位杂交(FISH)和免疫荧光(IF)数据 组织切片显示，RSPO2在增殖的远端上皮祖细胞附近表达， RSPO2受体LGR5几乎只在上皮祖细胞中表达。这些数据 提示RSPO2+间充质细胞可能在调控上皮祖细胞中起关键作用。 人类的肺发育。这项建议的目标是：1)询问间充质细胞的异质性和 在发育中的人肺中上皮祖细胞调节的作用和2)解释一种 RSPO2+间充质细胞在人肺发育中的功能作用。

PROJECT ABSTRACT Mammalian respiratory system development is regulated by complex reciprocal signaling events that take place between the epithelial cells lining the airways and the surrounding mesenchymal cells. Despite the lung mesenchyme being home to cell types that provide crucial signals during development, the identity and function of specific cell types in the lung mesenchyme are poorly defined, especially in the context of human development. To interrogate mesenchymal cell heterogeneity in the developing human lung, our lab has conducted single cell RNA sequencing on multiple human lung samples spanning 8-22 weeks of gestation. Using cell-clustering approaches, we identified a mesenchymal cell population highly enriched for expression of the WNT agonist R-Spondin2 (RSPO2). Strikingly, mutations in this gene cause severe lung aplasia in humans. My co-fluorescent in situ hybridization (FISH) and immunofluorescence (IF) data from human lung tissue sections show that RSPO2 is expressed adjacent to proliferating distal epithelial progenitor cells and that the RSPO2 receptor, LGR5, is expressed almost exclusively in the epithelial progenitor cells. These data suggest that RSPO2+ mesenchymal cells may have a critical role in regulating epithelial progenitor cells during human lung development. The goals of this proposal are to: 1) interrogate mesenchymal cell heterogeneity and function in the context of epithelial progenitor cell regulation in the developing human lung and 2) explain a functional role for RSPO2+ mesenchymal cells during human lung development.